The gang on “How I Met Your Mother” will return for a ninth and final season. (ERIC MCCANDLESS/FOX)

CBS was finally able Wednesday to make it official: “How I Met Your Mother” is coming back for one, final, and this time they mean it, season.

All series regulars — Josh Radnor, Jason Segel, Cobie Smulders, Neil Patrick Harris and Alyson Hannigan, and show creators Carter Bays and Craig Thomas — are back for a ninth season, at the end of which, CBS swears, the Dad/narrator will reveal to his kids — to whom he has been telling this longest of bedtime stories — who is Mom in this narrative.

Not that it matters because Dad’s kids were, several seasons ago, doomed to years of therapy, beecause, let’s face it, over its nearly eight seasons to date, Dad has been something of a hound dog, and don’t even get us started on the Mom candidates.

Squeezing a ninth season out of this sitcom was a priority for CBS. Despite all the “long in the tooth” blah, blah, blah from The Reporters Who Cover Television, “HIMYM” last season (its seventh) scored its best numbers ever among viewers (nearly 10 million of them), and among both 18-49 year old and 18-34 year old viewers. Most importantly, HIMYM has the youngest median age of any CBS series – 44.2 years.